Between 1969 and 1972, two humans at a time spent brief intervals on the Moon.

Perhaps all humans should spend a week confined like this, to get an idea what life is like for others.

Those humans who are surviving most successfully, now spend time considering the welfare of other creatures.

That's the way humans had always spent their time between the stars.

Why do humans spend so much time worrying about what they call "moral issues"?

Some humans spend their entire lives searching for the smallest glimmer of those secrets.

The researchers discovered a number of intriguing things about how ancestral humans may have spent their dark winter nights.

I thank the Giver that humans spend most of their time at each other's throats.

The tragedy, following this theory, is that humans spend all their time trying not to be human.

Believe me, humans will spend hours debating such things.